This invention pertains to wireless networking systems and, more particularly, to a wireless network access point which provides the resources of a backbone network to wireless clients. The access point is able to detect a degraded condition on the backbone network and autonomically dissociate clients thereby forcing clients into association with alternative access points having improved backbone connectivity.
Within the past two decades, the development of raw computing power coupled with the proliferation of computer devices has grown at exponential rates. This phenomenal growth, along with the advent of the Internet, has led to a new age of accessibility to other people, other systems, and to information.
The simultaneous explosion of information and integration of technology into everyday life has brought on new demands for how people manage and maintain computer systems. The demand for information technology professionals is already outpacing supply when it comes to finding support for someone to manage complex, and even simple computer systems. As access to information becomes omnipresent through personal computers, hand-held devices, and wireless devices, the stability of current infrastructure, systems, and data is at an increasingly greater risk to suffer outages. This increasing complexity, in conjunction with a shortage of skilled information technology professionals, points towards an inevitable need to automate many of the functions associated with computing today.
Autonomic computing is one proposal to solve this technological challenge. Autonomic computing is a concept to build a system that regulates itself much in the same way that a person's autonomic nervous system regulates and protects the person's body.
Within the past decade, there has been accelerated growth in portable computing to meet the demands of a mobile workforce. This voluminous mobile workforce has traditionally relied on a cable connection to a backbone network in order to have access to resources such as printers, e-mail servers, databases, storage, and even Internet connections. Within the past few years alone, the industry has seen rapid deployment of wireless local area networks which offer increased convenience over cable connections to backbone networks. In addition to convenience, wireless networks offer the ability to roam while maintaining a network connection.
Recently, a standard for wireless local area networks known as the IEEE 802.11 standard has been adopted and has gained acceptance among the industrial, scientific and medical communities. The IEEE 802.11 standard for wireless networks is a standard for systems that operate in the 2,400-2,483.5 MHz industrial, scientific and medical (ISM) band. The ISM band is available worldwide and allows unlicensed operation of spread spectrum systems. The IEEE 802.11 RF transmissions use multiple signaling schemes (modulations) at different data rates to deliver a single data packet between wireless systems.
In a wireless local area network, wireless clients obtain access to resources on the backbone network through the use of an access point. The backbone network is typically on a wired network, such as ethernet, but can also be a second wireless network or any combination thereof. When an access point provides connectivity to resources directly on a wired network, the access point will contain, amongst other things, a wired LAN interface, a bridge function, and a wireless LAN interface in order to bridge traffic between the wireless network and the wired network.
Most installations use wireless local area networks as an overlay to an existing ethernet (cabled or wired) network which serves as a backbone or provides access to a backbone and its resources. Typically, access points are provided at various locations to create continuous geographical coverage for the wireless network. Since 802.11 is limited to 30 meters in range and Ethernet is physically limited to 100 meters in length, office environments typically deploy several access points on different backbones. The various wireless access points are assigned to different wireless frequency spectra or channels to allow overlap between wireless ranges.
Constituent components of an access point typically include a LAN interface, a LAN hub, a bridge function, and a wireless LAN interface. Software is executed for performing router and network address translation functions. The constituent components typically act as independent units, i.e., peer-to-peer LAN, LAN backbone, and as independent peer-to-peer wireless LAN, for example. This independent operation of access point components allows for the access point to be very flexible.
A problem emerges, however, as a result of this independent operation of access point components. When a first ethernet backbone goes down the wireless LAN interface component of the access point continues to operate by providing independent peer-to-peer wireless LAN functionality. As such, wireless peer-to-peer clients are able to share mapped drives and other resources found on the wireless network. However, users connected to the access point are unable to reach network resources found on the first ethernet backbone. Meanwhile, another client in the same physical area which happens to be connected to a different access point which is connected through a second ethernet backbone can remain operational with full access to backbone resources. This resulting inconsistency in network resource availability is problematic because it raises the level of frustration for the users affected and raises the cost of computing as a direct result of increased help center calls.
A challenge found, however, is in mitigating this inconsistent network availability of clients according to autonomic computing principles.